Barton, then at Newcastle, was involved in another controversial incident on the opening day of the season, when he admitted "going down easily" in an altercation which led to Arsenal forward Gervinho being shown a straight red card.

Supporting the Rangers captain for his role in the latest incident, Warnock called for Johnson to be punished, but was not optimistic that Barton's red card would be overturned if QPR decided to appeal.

"He has not been headbutted at all, not in a million years," said the Rangers manager as he reflected on Johnson's reaction. "The movement of him going backwards has conned the referee.

"To go back like he did was a disgrace. It's getting a fellow pro sent off. I think he should be [punished].

"We will have to look and see what the referee says in his report and if there are any other angles, but from every one I have seen, I don't see a headbutt.

"We will have to decide later. I have not got any confidence in the appeals procedure. I am not optimistic."

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